In wet grinding, the consistency or viscosity

 

The smaller the Mill the faster in RPM it must run to attain critical speed.

 

 

For most grinding and dispersing problems, we strive to attain the cascading, sliding action described earlier, and to accomplish this we have found that the most desirable angle of break ranges from 50 to 60 degrees from the horizontal.

 

The lower range is recommended for most wet grinding operations like paints and soft dry materials, and the higher break point (which provides a more severe grinding action) for most dry materials and wet grinding such hard products as enamel frit and glaze.

 

It is also known that the grinding action in a larger mill is more severe than in the smaller sizes and, consequently, we are of the opinion that the angle of break should be lower for the larger Mills than for the smaller.